An electromagnetic flow sensor can be used to detect fluid flow through a conduit. A constant excitation current can be delivered to a coil, which can generate an electromagnetic field in the conduit. A response signal can be detected by sensing electrodes of the electromagnetic flow sensor. The response signal can include information about the fluid flow. A sensor interface circuit can be used to provide control signals to generate a coil excitation current and to provide signal processing of the response signal. For example, U.S. Pat. No. 6,693,486 includes an example of a magneto inductive flowmeter interface circuit.